Process of making depolarizers



Oct. 25, 1932. BR1GG$ 1,884,554

PROCESS OF MAKING DEPOLARIZERS Original Filed March 31. 1922 PatentedOct. 25, 1932 FEM) ARTHUR 3'. BRIGGS, OF SYRACUSE, NEW YORK, ASSIGN 01TO NATIONAL CARBON COMPANY, INC. A GDRPORATIOH GE l-IIEVI YORK PROCESSOF MAKING DEEGLAEEZERS Original application filed March 31, 1922, SerialNo. 548,429. Divided and this application filed June 15, 1927.

. Serial No. 199,939.

This invention relates to the manufacture of depolarizers for dry cells,and more particularly to improved procedure and apps.- ratus forpreparing such depolarizers. This application is a division ofapplication Serial N 0. 548,420, filed March 81, 1922, wherein theimproved depolarizer is disclosed and claimed.

- The objects of this invent-ion are to improve the quality ofdepolarizer bodies, to provide new forms thereof, and to decrease thecosts and time of manufacture. lhis invention contemplates theapplication of extrusion apparatus and processes to the production ofdepolarizer bodies.

It has heretofore been proposed to prepare tubular mix bobbins byextrusion, to force a cylindrical carbon electrode into the perforationthrough each bobbin while the composition retains its plasticity, and towrap each bobbin in a suitable fabric subsequent to the insertion of theelectrode. In following such procedure, a large percentage of bobbins isbroken, because the unsupported depolarizing material'is easilydisruptedby the out ward pressure exerted by the electrode forced into thecentral opening in the bobbin.

'Acoording to the present invention, the depolarizing material iscompacted and extruded as an clongatedbody having one or more holesextending lengthwise therethrough. This compacted elongated body isadapted to be cut transversely into a number of individual depolarizers,but prior to the severing operation the elongated body is pcripherallyreinforced, as by mechanically applying a wrapping thereto or coatingthe same with a suitable paste or adhesive substance, such wrappingand/or substance being preferably applied as the depolarizer compositionis extruded. In the improved method, the covering or coating thatengages the peripheral surface of the extruded body sustains orreinforces the latter during handling and during the cutting operation,thus reducing any tendency of the cutter or other mechanism to damagethe main body or the individual depolarizers. Moreover, suchreinforcement is also advantageous where carbon electrodes are insertedin the holes of the individual bodies, since a carbon electrode ofsullicient size to insure adequate electrical connection betweendepolarizer and electrode may be inserted in the reinforced depolarizerwithout danger of damaging or destroying the depolarizer body or bobbin.

The objects and novel features of this in vention will be apparent fromthe description and the accompanying drawing, which illustrates theinvention as applied to the manufacture of well-known type ofdepolarizer body. In the drawing,

l is lon itudinal section through an extrusion and wrapping machine,

' 2 is a longitudinal section through a ed extrusion die,

on line 33 Fig. 3 is a transverse section of .2,

Fig. l is a perspective view of a wrapped body of mix, and

Figs. 5 and 6 show mix bobbins provided with a plurality of verticalperforations, the former figure in elevation and the latter intransverse section.

Referring to 1 of the drawing, plastic depolarizing material 1 is forcedforwardly through the funnel shaped member 2, preferably bysubstantially constant pressure deived from any suitable source. Thefunnel terminates in a tubular extension 3 which \.rates as a die informing an extruded body of he chosen diameter. W hen it is desired toprovide the body with a cylindrical perforation, a core for the dieconsisting of a rod l of suitable cross-section is mounted in a spider 5rigidly attached to the funnel wall. The rod 4 tends outwardly wellbeyond the tubular ension 3 and is preferably coaxial with theextension. The extended portion of the rod serves to support theextruded body during the Wrapping operation.

The means for applying a protective wrapping to the extruded bodycomprises a reel carrier 6, journalled on extension 3 and held thereonby any suitable means. The carrier is adapted to be rotated about thelongitudinal of the extruded body by means of a pulley 7, driven by belt8. in inclined reel 9 is mounted upon an arm 10, integral with carrier6. The arm 10 carries a bracket 11 to which is secured a guide rod 12extending in close parallel relation to the extruded body. The fabric orother material 13 carried by the reel passes between the guide rod andthe extruded body.

Rotation of the carrier 6 causes the fabric carried by the reel to becontinuously drawn off and wrapped in an overlapping helix about theextruded mix. Guide rod 12 presses the fabric toward the mix to insuretight wra pin". If desired, the guide rod may be ma e ad ustabIe so asto permit regulation of the tension at which the fabric is supplied. Itmay be stated that the term fabric, as used herein, respecting therelatively wide continuous sheet or band 13 is to be considered genericto all of the bibulous materials which are suitable for wrapping mixbobbins.

The preferred means for securing the fabric about the mix comprises acontainer 1% arranged to discharge a regulated stream of paste or otheradhesive material. A wiper 15, rotated by a pulley 16, engages thewrapping and uniformly'distributcs upon it the material supplied fromcontainer 1 1-. The pulley 16 is preferably integral with an extension17 keyed to a cylinder 18. Surrounding the major portion of the cylinder18 is a heating chamber 19, in which the adhesive is hardened. Gasflames 20 or any other suit able source of heat may be supplied in theheating chamber. In the arrangement shown, belt 21 rotates the cylinder18, so as to }present all parts of its surface to the source of cat.

Instead of pasting the fabric, it maybe secured by tying or the like- Insome cases, also, the fabric may be omitted, and paste or other suitablematerial adapted to harden upon the bobbin surface may be applieddirectly thereto.

Any desired means for severing the elongated tubular body may beadopted. An eccentrically'mounted cutting disc 22 has been illustratedbyway of example. The severed portions may be delivered to packing devicesor otherwise disposed of. If the product is wrapped depolarizing mix,carbon rods may be inserted by hand or the tubular sections may be fedinto any suitable type of machine for automatic insertion of the rods. Awrapped bobbin so prepared is illustrated in Fig. It will be noted thatthe ends of the b0 bin are not covered. For many purposes the bobbin maybe left in this condition, but discs of paper or the like may of coursebe placed over the ends, if desired. An advantage of the improved bobbinis the elimination of the objectionable bunching of fabric about theprojecting end of the carbon rod,

common to prior wrapped bobbins.

In the modified form of the invention illustrated in Figs. 2 and 3, aplurality of slender rods 23 are seated in the spider 5 and pass throughextensions 3 in parallel relation to the core rod 4;. This arrangementis especially designed for the production of mix bobbins for use indeferred action cells of the water activated type. The numerousperforations formed in the mix, by forcing it about rods 23, permitrapid absorption and even distribution of the activating liquid. Abobbin of this type, with cylindrical vertical openings 24, is shown inFig. 5. Perforations 24, of a different shape, are illustrated in Fig.6. Obviously the size, shape and location of the perforations may begreatly varied. They may be very conveniently made during the extrusionoperation, as described, but may also be formed in other ways. Forexample ordinary tamped bobbins, or the extruded bobbins describedherein, may be punched or bored to give the desired number of openings,and these need not extend entirely through the bobbin.

The cylindrical conformation of the bobbin and its axial perforation isshown by way of example only, as the shape of the extruded body may bevaried according to its intended use. It is preferred to extrude theplastic material continuously, but an intermittent feed may be used, thewrapping and severing devices being synchronized with the movement ofthe extruded body. Various other departures from the specific formillustrated herein fall within the scope of the appended claims.

I claim:

1. Process of making depolarizing bobbins which comprises shaping thedepolarizing material, applying a supporting depolarizer covering aroundthe shaped material, and then inserting an electrode into the coveredbody.

2. Process of making depolarizing bobbins which comprises shaping thedepolarizing material into an elongated body having a central holetherethrough; applying a protective reinforcement around the lateralsurface of said body; severing said body at intervals in its length soas to produce a plurality of laterally reinforced and centrallyapertured sections; and then inserting electrodes into the apertures ofsuch sections.

3. Process of making depolarizer elements for dry cells which comprisesextruding depolarizer material through a die so as to form an elongatedbody with a central hole therethrough, applying a surface reinforcementaround the material exteriorly of the die, supporting the body fromwithin during the reinforcement, removing the support, dividing thecovered body into sections and inserting an electrode into each coveredsection.

4. Process of making depolarizer elements for dry cells which comprisesextruding depolarizer material through a die so as to form an elongatedbody with a central hole therethrough, continuously applying a surfacereinforcement around the material exteriorly of the die, continuouslypassing the material over a centrally disposed support during thereinforcement, removing the support, dividing the covered body intosections and inserting an electrode into each covered section.

In testimony whereof, I aflix my signature.

ARTHUR J. BRIGGS.

